The Effect of Different I:E Ratio on Gas Exchange of Patients Undergoing Gynecologic Laparoscopic Surgery With Trendelenburg Position

Samsung Medical Center

Status: Completed

Conditions: Ovarian Cyst; Laparoscopic Gynecologic Surgery; Uterine Myoma

Treatments: Procedure: 1:1 ratio; Procedure: 2:1 group; Procedure: external PEEP; Procedure: conventional I:E ratio

Study type: Interventional

Funder types: Other

Identifiers

NCT01379313

2011-04-007

Details and patient eligibility

About

In patients undergoing gynecologic laparoscopic surgery with trendelenburg position, the disturbance of pulmonary gas exchange frequently occurs due to high intra-abdominal pressure. The investigators tried to evaluate the effect of various inspiratory to expiratory ratio on pulmonary gas exchange by randomized controlled trial.

Full description

In patients undergoing gynecologic laparoscopic surgery with trendelenburg position, the disturbance of pulmonary gas exchange frequently occurs due to high intra-abdominal pressure. During the laparoscopic surgery with abdominal gas insufflation, gas exchange disturbance such as CO2 retention, hypoxemia occurs in addition to high plateau airway pressure. The usual strategy against these kinds of problem is pressure-controlled ventilation. However, the gas exchange problem especially CO2 retention can not be solved in some cases. The inverse-ratio ventilation (IRV), which prolongs the inspiratory time greater than expiratory time, can be applied for adult respiratory distress syndrome. The efficacy of IRV is to improve gas-exchange status by increasing mean airway pressure and alveolar recruitment. There have been several clinical investigations which applied IRV during general anesthesia. However, there have been debates about the effect of IRV during general anesthesia. Therefore, we tried to apply the IRV for subjects undergoing laparoscopic surgery, and evaluate the effect of different I:E ratio on the pulmonary gas exchange and respiratory mechanics.

Enrollment: 100 patients

Sex: All

Ages: 20 to 65 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• patients undergoing elective gynecologic laparoscopic surgery
• the duration of pneumoperitoneum during laparoscopic surgery is more than 40 minutes

Exclusion criteria

• ASA (American society of anesthesiologists) classification of the subjects more than III.
• Age under 20, or more than 65 years.
• Past history of pneumothorax, COPD, asthma.
• Patients with ischemic heart disease, valvular heart disease.

Trial design

100 participants in 4 patient groups

1:2 group

Active Comparator group

Description:

conventional I:E ratio group, inspiratory time : expiratory time = 1:1

Treatment:

Procedure: conventional I:E ratio

1:1 group

Experimental group

Description:

1:1 I:E ratio group, inspiratory time : expiratory time = 1:1

Treatment:

Procedure: 1:1 ratio

2:1 group

Experimental group

Description:

inverse ratio group, inspiratory time : expiratory time = 2:1

Treatment:

Procedure: 2:1 group

1:2 PEEP group

Active Comparator group

Description:

I:E ratio of 1:2 with external PEEP of 5 cm H2O

Treatment:

Procedure: conventional I:E ratio

Procedure: external PEEP